The present invention relates generally to the field of voice communication devices; and deals more specifically with a microphone assembly for adhesive attachment to an external surface of a face mask or other vibratory surface excited by human voice.
The microphone assembly of this invention is especially well suited for use in combination with a face mask wherein it is attached to an external surface of the mask vibrated by the voice of the person wearing the mask. The microphone assembly of the invention is therefore illustrated and described herein for convenience in connection with such application. It is to be understood, however, that use of the subject microphone assembly is not limited to face masks and that it may instead find use with other vibratory surfaces excited by human voice or by other sources with frequencies similar to those of human voice.
Face masks known in the prior art are commonly used by persons working in contaminated or hazardous atmospheres such as those sometimes found, for example, in nuclear material handling facilities or in fire fighting situations. These masks usually cover both the nose and mouth of the wearer and by some means permit the wearer to breathe while working with the mask in place.
It is often desirable that persons wearing masks of this type be able to communicate with other persons either nearby or at some remote location, and to meet this need various attempts have been made in the past to provide microphones for face masks to pick up the voices of the wearers and to convert the voice signals into electrical signals which are then amplified and transmitted by radio or other means to other persons or locations. Often these microphones are designed to be located inside of the face mask, which gives rise to problems in leading wires from the microphone to the outside of the mask without leakage of the surrounding atmosphere into the mask. Also the masks are often worn in noisy environments and it is desirable that the microphones used with them be relatively sensitive to the voices of the wearers while at the same time being relatively insensitive to background or ambient noises. Still further, if the masks are used in polluting or dirty atmospheres it is often necessary to periodically clean them and the associated microphones by perhaps washing them with water or other cleaning liquids, and the microphones accordingly should be ones capable of being immersed in the cleaning liquids without damage.
The general object of the invention is therefore to provide a microphone assembly for attachment to a member, such as the window of a face mask, vibratorily excitable by a human voice, to convert the vibrations of that element into electrical signals corresponding to the human voice signals and which microphone assembly overcomes the problems mentioned above.
A further object of the invention is to provide a microphone assembly of the foregoing character which is readily adhesively attachable to a face mask to pick up the wearer's voice without any special modification or adaptation of the face mask being required. In keeping with this object a more specific object of the invention is to provide a microphone assembly which can be readily attached to and removed from a face mask to allow the assembly to be removed and reattached to the face mask for cleaning purposes, to be removed for replacement by another assembly, or to be removed for reattachment to another face mask.
Other objects and advantages of the invention will be apparent from the following detailed description of a preferred embodiment and from the accompanying drawings and claims.